Human Speech System

How do humans generate the sounds that we recognize as speech? Airflow from LUNGS to VOICE BOX to VOCAL TRACT. Simplified.

When we breathe, air flows through our lungs and voice box, which allows us to speak. The vocal tract is the pathway that air travel through from the lungs to the voice box. The shape of the vocal tract affects the quality of our speech.

Types of Vocal Cords

There are two types of airflow: laryngeal and lung. Laryngeal airflow is produced by the larynx, and lung airflow is produced by the lungs. The larynx is responsible for producing sound, while the lungs provide the power to create airflow.

The vocal tract can be divided into three parts: the mouth, the pharynx, and the larynx. The mouth is the beginning of the vocal tract, and the larynx is the end. The pharynx is the section in between.

The mouth is responsible for shaping the airflow. The lips, teeth, tongue, and palate can all influence the shape of the airflow. The airstream then goes through the pharynx, where it is further shaped by the soft palate and pharyngeal walls. Finally, it reaches the larynx, where the vocal cords vibrate to produce sound.


The vocal tract is a complex system, and the quality of our speech depends on many factors, including the type of airflow, the shape of the vocal tract, and the way the airstream is produced. The lungs are responsible for the intake and release of air. The voice box is responsible for the production of sound. The vocal tract is responsible for the shaping of the sound.